Planning Pregnancy With Ulcerative Colitis

If you have ulcerative colitis (UC) and want a baby, the single most useful thing you can do is plan the timing around your colitis rather than around the calendar. The first global consensus on pregnancy in inflammatory bowel disease, published in 2025, asks for documented remission for 3 to 6 months before conception, a medicine plan that suits pregnancy, and a preconception conversation with your IBD team, ideally about six months before you start trying (Mahadevan 2025). "Documented" is doing a lot of work in that sentence: it means steroid-free and confirmed with tests, not just feeling fine.

The rest is more reassuring than most people expect. Fertility with medically treated UC is close to normal. Most maintenance medicines are meant to continue through conception and pregnancy. The risks that do exist mostly come from inflammation, which is the thing planning lets you get ahead of. This guide is the before-conception half of the story. What happens to UC once you are pregnant, including flares, monitoring and the postpartum window, has its own article on UC flares during pregnancy, and we link to it rather than repeat it.

We built this article from the full text of the 2025 consensus, the fertility and preconception studies it rests on, and four r/UlcerativeColitis threads where people planning or recovering from pregnancies compared notes. Where a number in the literature does not add up, we say so. This is general information, not advice for your situation, and nothing here is a reason to stop or change a medicine on your own.

What does "in remission before pregnancy" actually mean?

It means steroid-free remission that a test confirms, held for roughly 3 to 6 months. The consensus describes the target in plain terms: an assessment of symptoms, then confirmation with objective markers, "steroid-free clinical remission as well as biochemical remission" with a faecal calprotectin below 150 µg/g and a normal C-reactive protein (CRP). Endoscopy or imaging such as intestinal ultrasound is added depending on how severe your disease has been, and drug levels are checked where that is local practice for your medicine (Mahadevan 2025). The document calls this "documented remission" and pairs it with being "medically optimized", meaning you are on a therapy that works for you, at adequate levels, that you can stay on.

Three things in that definition trip people up.

Feeling well is not the bar. UC can look settled on symptoms while calprotectin is still raised, which is why the consensus insists on a test. If you are unsure how your own numbers read, our guide to what calprotectin levels mean in UC explains the thresholds and why a single value can mislead. It is also worth knowing that mild symptoms can persist with no inflammation at all, which is covered in UC symptoms while in remission. Planning conversations go better when you know which of those two situations you are in.

Steroids do not count. A course of prednisolone or budesonide that has calmed a flare has not established remission in the sense the consensus means. The point is to be well on the medicine you will stay on.

The 3 to 6 months is a target, not a rule written in stone. In the r/UlcerativeColitis thread "Planning to become pregnant, what did you do?", people reported being told six months, six to twelve months, and one year by their own gastroenterologists (r/UlcerativeColitis). Those are stricter versions of the same idea, not contradictions. The consensus also says plainly that a small number of people cannot achieve sustained remission despite optimised treatment, for example with hard-to-control disease at an older maternal age, and that for them it is appropriate to get disease control as good as realistically possible rather than wait indefinitely (Mahadevan 2025).

Why the timing matters so much

Disease activity around conception is the strongest predictor of disease activity during pregnancy. A Danish tertiary-centre cohort of 609 pregnancies in women with IBD found that activity in the 6 months before conceiving (present in 27.7%) carried an adjusted odds ratio of 5.3 (95% CI 3.5 to 8.2) for continuous activity during pregnancy. UC itself, compared with Crohn's, was associated with more activity in pregnancy (adjusted OR 2.6), and activity in a previous pregnancy predicted flares in the next one (adjusted OR 3.2). The same study found that women who stayed in clinical remission had birth outcomes similar to normal (Vestergaard 2023).

That fits an earlier meta-analysis showing that conceiving with active IBD made active disease during pregnancy considerably more likely (Abhyankar 2013). Our pregnancy flare article walks through those numbers and the outcomes linked with active disease, so we will not rebuild them here. For planning, the takeaway is simple: the months before conception are the part of this you have the most control over.

Does preconception counselling actually change anything?

Yes, probably, and it is the one recommendation the consensus rates "strong". GRADE statement 7 recommends that women with IBD receive preconception counselling, a strong recommendation on low-quality evidence (Mahadevan 2025). Most of the document's other statements are conditional, so this stands out.

The main study behind it comes from a dedicated preconception IBD clinic in Rotterdam. It followed 155 women seen before they became pregnant and compared them with 162 who were first seen once already pregnant. Preconception care was associated with medication adherence during pregnancy (adjusted OR 5.69), adequate folic acid intake (adjusted OR 5.26), stopping smoking (adjusted OR 4.63) and fewer relapses during pregnancy (adjusted OR 0.51, 95% CI 0.28 to 0.95), independent of parity, disease duration and disease activity before conception (de Lima 2016).

Two honest limits. First, this is not a randomised trial. The two groups differed at baseline: the preconception group was younger (29.7 versus 31.4 years) and more often having a first baby (76.1% versus 51.2%), and people who seek advice before conceiving may differ in other ways no adjustment captures. Second, the study's headline about low birth weight is less solid than it reads.

Other evidence points the same way, mostly through knowledge and adherence:

• A single conversation shifts knowledge. In an Australian study of 100 women with IBD who were pregnant or planning, one gastroenterologist-led education session raised median scores on the Crohn's and Colitis Pregnancy Knowledge questionnaire from 10 to 14 out of 17, and cut the share with poor knowledge from 32% to 5%. Anxiety, depression and quality-of-life scores improved too (Flanagan 2021).
• Counselling predicts adherence. In a Danish study of women with UC who gave birth between 2000 and 2005, those counselled about their treatment were less likely to stop taking it during pregnancy (prevalence OR 0.2). Among those who did not adhere, fear of harming fertility or the baby was the stated reason for 23% before pregnancy and 50% during it (Julsgaard 2011).
• Adherence slips even in people who were adherent. In a Canadian administrative-data study, of 159 women who took their IBD maintenance medicine reliably in the year before pregnancy, 20 became non-adherent and 21 stopped during pregnancy, which is 41 of 159, or about a quarter (Lee 2020). The same abstract also reports drug-class adherence percentages (41.5% for biologics, for example) that we could not square with that quarter from the abstract alone, so we have not used them.

The pattern behind all of this is fear filling a gap that information would fill. People on Reddit describe being told by a GP to stop mesalamine, or reading "not tested in pregnancy" on a box and worrying for months (r/UlcerativeColitis). A planned conversation is where those worries get answered before they turn into a decision.

A timeline for the year before you try

Start the conversation earlier than feels necessary, because changing a medicine and proving it works takes months. The consensus says counselling should ideally happen at least six months before trying, and that education about pregnancy should start at diagnosis for anyone of reproductive age and come up again with every new medicine (Mahadevan 2025). Here is how its recommendations line up on a calendar. Your team may sequence it differently.

The last row is worth noticing. The consensus checklist suggests a fertility review if you are not pregnant after 6 months of timed intercourse (Mahadevan 2025). It does not explain the choice of six months in the text we read, but the logic fits the rest of the document: a period of good disease control is not guaranteed to last, so it makes sense not to spend too much of it waiting.

The "wait for the right month" trap

One r/UlcerativeColitis post describes a situation that the timeline cannot fully prevent. After 1.5 years of remission and a doctor's go-ahead, the poster and their partner delayed trying by a few months for a holiday, and the colitis started flaring in the gap. Their fear was being moved to a medicine they could not conceive on (r/UlcerativeColitis). Nobody can promise remission will hold, and there are often good non-medical reasons to wait. But if you have reached the point your team considers ready, it is worth knowing that the window is real, and having the conversation about what happens if it closes before you start, rather than after.

Your medicines are the main job

For most people with UC, the medicine plan is the biggest single piece of preconception work, and for most maintenance medicines the answer is to keep taking them. The consensus states that its guiding principle is that "maternal health best supports infant health", and its consensus statement 32 calls controlling disease activity in pregnancy "critical to reduce adverse outcomes" (Mahadevan 2025).

Source for every row: the GRADE and consensus statement tables of Mahadevan 2025.

A few things that table does not tell you on its own:

Switching takes longer than the washout. If you are on a small-molecule drug, the stop window is only part of the timing. The consensus checklist asks for "established remission on new therapy" after stopping a potentially harmful medicine, which means waiting until the replacement has proven itself. That can take months, and it is the main reason to raise pregnancy plans early.

The "unless no effective alternative" clause is real. One r/UlcerativeColitis poster described failing a series of biologics, reaching remission only on upadacitinib, staying on it through pregnancy with their gastroenterologist's agreement, and delivering a healthy baby (r/UlcerativeColitis). That is one person's account and not evidence of safety. It does show what the consensus wording allows: a decision made with your team, weighing an unproven medicine against uncontrolled colitis, rather than an automatic ban.

Steroids are a treatment, not a plan. The consensus suggests corticosteroids can be used in pregnancy when clinically necessary, with monitoring (Mahadevan 2025). But steroid-dependence is the opposite of the steroid-free remission it asks for before conception. One person on Reddit also described prednisone stopping their periods while they were trying, which is anecdote, but a reminder that a body in a flare is not in its usual state (r/UlcerativeColitis).

Check your mesalamine formulation. Some older delayed-release 5-ASA products used dibutyl phthalate (DBP) in their coating. Phthalates have caused reproductive and developmental effects in animal studies, which led to calls for doctors to review the coatings in medicines taken by pregnant women with IBD (Gallinger 2013). The 2025 consensus says current commercially available aminosalicylates do not contain DBP (Mahadevan 2025). It does not list products by country, and formulations vary, so if you take mesalamine it is a reasonable question for your pharmacist rather than a reason to stop.

Rectal treatment is allowed. The consensus notes that mesalamine enemas can be used in pregnancy, especially with mainly rectal symptoms such as urgency and tenesmus. Several people in the threads described getting through pregnancy on suppositories or enemas.

Low-dose aspirin is coming up. Once you are pregnant, the consensus suggests women with IBD take low-dose aspirin by 12 to 16 weeks of gestation to reduce the risk of preterm preeclampsia (conditional, low-quality evidence). Because anti-inflammatory painkillers have historically been linked with IBD flares, some people worry about this, and one Reddit poster felt aspirin worsened their colitis and stopped it (r/UlcerativeColitis). The consensus reviews this directly: in one single-centre study it describes, clinical flares in pregnancy occurred in 16.9% of 71 women taking low-dose aspirin and 14.4% of 313 who were not (P = 0.6), and it concludes flares do not seem to be triggered by low-dose aspirin in pregnancy, while calling the data sparse (Mahadevan 2025). It is worth knowing in advance so the obstetric and IBD teams can discuss it together, not something to start on your own.

Will UC make it harder to get pregnant?

Not much, if the colitis is controlled. What reduces fertility is active disease and certain kinds of surgery. The consensus suggests counselling women with IBD that fertility "may" be somewhat decreased compared with women without IBD, a conditional statement on very low-quality evidence, and it recommends, as a strong statement, counselling that active disease increases the risk of infertility compared with inactive disease (Mahadevan 2025).

The population numbers for UC specifically are close to normal:

• Sweden. A national cohort of 27,331 women with IBD and 131,892 matched women found the chance of giving birth was barely lower in UC (hazard ratio 0.96, 95% CI 0.93 to 0.98), against 0.88 in Crohn's disease. Fertility in UC improved over the study period, and women with IBD used contraception more often both before and after diagnosis (Druvefors 2021).
• UK. A primary-care cohort of 9,639 women with IBD found that after diagnosis, the adjusted fertility rate ratio for UC was 0.92 (95% CI 0.86 to 1.00). When periods of contraceptive use were excluded, the overall IBD figure rose to 0.99, essentially normal (Ban 2015).
• Systematic review. Fourteen studies covering 18,012 women with UC who had not had surgery found fertility comparable to the general population, with women with UC tending to have fewer children "mainly by choice" (Vieujean 2023).

Inflammation is what lowers fertility

Flares, and even inflammation you cannot feel, are linked with fewer conceptions. In the UK study, fertility was lower in the period after flares (rate ratio 0.70) and after surgery (0.84) (Ban 2015). A Swedish nationwide study went further, linking fertility with biopsy results. Clinically active UC was associated with a fertility rate ratio of 0.75. Among women whose IBD was clinically quiet, inflammation seen only under the microscope was still linked with lower fertility (rate ratio 0.85, 95% CI 0.73 to 0.98). The authors translated the clinical-activity finding into one fewer child per six women with ten years of active disease (Mårild 2024). The consensus notes that this study did not have matching endoscopy, blood or imaging data, so it cannot say whether biopsy inflammation adds anything beyond those.

Ovarian reserve, the pool of eggs a fertility clinic estimates with anti-Müllerian hormone (AMH), points the same direction. A meta-analysis of nine studies found women with IBD had lower AMH overall, but those in remission had ovarian reserve similar to controls while those with active disease had markedly lower levels. Women under 30 showed no clear decline, and women over 30 did (Sun 2022). The data were heterogeneous and mostly from Crohn's disease, and the consensus cautions that AMH cannot predict fertility and should only be used in the context of assisted reproduction (Mahadevan 2025). Treat it as one more reason remission matters, not a test to order on your own.

Choosing not to have children, and why knowledge matters

Women with IBD are more often childless by choice, and some of that choice rests on misinformation. The first study to describe this surveyed 169 women with IBD in Illinois and found voluntary childlessness of 18% in Crohn's and 14% in UC, against 6.2% in the general population (Marri 2007). Its title says voluntary childlessness is increased, but the UC difference was not statistically significant (P = 0.08), and the authors attributed the gap more to education and demographics than to IBD itself.

A larger UK survey of 1,324 women from Crohn's and Colitis UK found 17% were voluntarily childless. That group had lower pregnancy knowledge scores (5.98 versus 7.47 among women planning children), more hospital admissions and more surgery. The authors concluded that women "may stay childless unnecessarily" and that education could correct misconceptions (Selinger 2016). Not wanting children is a perfectly good decision. Deciding against them because of a belief that UC makes pregnancy impossible or that the medicines are dangerous is a decision worth revisiting with better information.

How surgery changes the fertility picture

A colectomy itself has a modest effect, but a j-pouch or removal of the rectum lowers female fertility more clearly. The consensus suggests counselling women with UC that a previous ileal pouch-anal anastomosis (IPAA, the j-pouch) is associated with decreased fertility, a conditional statement on very low-quality evidence (Mahadevan 2025). The figures behind it:

• A meta-analysis of 13 studies, comparing the same women before and after pouch surgery, found the relative risk of infertility was 4.17 (95% CI 1.99 to 8.74) after the pouch (Sriranganathan 2022). The consensus adds that the pooled infertility rate was 13% before and 43% after, and that removing four heterogeneous studies reduced the relative risk to 2.96, still raised.
• A Swedish national study of 2,989 women with IBD and a previous colectomy found lower fertility overall after colectomy (HR 0.65). Compared with colectomy alone, fertility was not further reduced after an ileorectal anastomosis, where the rectum is kept (HR 0.86 in UC, 95% CI 0.63 to 1.17), but was reduced after a j-pouch in UC (HR 0.67) and after completion proctectomy (HR 0.65) (Druvefors 2023).
• The disagreement deserves mentioning. According to the consensus, a Cochrane review that applied strict inclusion criteria could include only two studies and found the effect of pouch surgery on fertility unclear. The UK study above also cautioned that its post-pouch reduction should be interpreted carefully because the lifetime difference between pouch and non-pouch surgery was small (Ban 2015).

The consensus says the likely mechanism is pelvic adhesions, and that there is no evidence to support freezing ovarian tissue before surgery (Mahadevan 2025). If surgery is on the table and you want children, the order of operations, the choice of reconstruction and whether to complete a family first are decisions for a surgical consultation. They are covered in depth in what I wish I knew before j-pouch surgery and compared head to head in j-pouch vs ostomy. If you already have a pouch, pregnancy with a j-pouch covers delivery and pouch function in pregnancy.

IVF and fertility treatment with UC

Assisted reproduction works for women with UC, though one large registry found a somewhat lower success per embryo transfer. The consensus suggests counselling that assisted reproduction is about as effective in women with IBD as in women without, measured by live birth, and that women who have had pelvic surgery for IBD have similar IVF success too. Both are conditional statements on very low-quality evidence (Mahadevan 2025).

The studies do not all agree:

• A meta-analysis found women with UC had no difference in pregnancy rates (OR 0.99) or live birth rates (OR 0.88, 95% CI 0.67 to 1.17) per cycle compared with the general population. Live birth rates were lower after a failed j-pouch (HR 0.36, 95% CI 0.14 to 0.92) (Laube 2021).
• A Danish nationwide registry of 1,360 treatments in 432 women with UC found the chance of a live birth per embryo transfer was lower than in women without IBD (OR 0.73, 95% CI 0.58 to 0.92). The authors suggested women with UC "cannot expect the same success for each embryo transfer" as other infertile women (Nørgård 2016).

Part of the difference is what is counted: per transfer, per woman within 18 months, or cumulatively after several cycles. The consensus describes a further Danish analysis suggesting that where success is lower, it is in achieving a pregnancy rather than carrying it to term.

Two practical points from the consensus are worth raising with a fertility clinic. It reports that the medicines usually continued during egg retrieval (5-ASA, thiopurines, biologics) have no data either way on stimulation, and the authors continue them in practice. And it flags that the S1P modulators ozanimod and etrasimod should be avoided alongside gonadotropin-releasing hormone agonists used in some IVF protocols, because both can prolong the QT interval of the heart (Mahadevan 2025). Fertility clinics do not always know IBD drugs well, so it helps if your IBD team and the clinic talk directly.

If you are the partner with UC

Men with UC have near-normal fertility, and the main medicine to know about is sulfasalazine. The 2025 consensus is about women, so this section draws on other studies. Several Reddit threads ask whether UC lowers sperm count, which is a real question deserving a real answer (r/UlcerativeColitis).

• Overall fertility. A Swedish national cohort of 29,104 men with IBD found a slightly lower chance of fathering a child with UC (hazard ratio 0.93, 95% CI 0.91 to 0.96). Disease severity was associated with further reductions (Druvefors 2022). After colectomy, fertility in men was only marginally reduced (HR 0.89), regardless of the type of reconstruction (Druvefors 2023).
• Sulfasalazine. In a study that combined men and rats, sulfasalazine caused low sperm counts, reduced motility and more abnormal sperm. The effects reversed after stopping, and 15 pregnancies followed at a median of 2.5 months after men came off it. The rat experiments pointed to the sulfapyridine part of the molecule, not the 5-ASA part (O'Moráin 1984). That is why men planning a family who take sulfasalazine sometimes discuss switching with their gastroenterologist. That is their decision to make together, not something to do alone.
• Mesalamine. A Danish nationwide study of 2,168 children fathered by men using 5-ASA before conception, mostly mesalazine, found no increased risk of preterm birth, small size for gestational age or low Apgar score. The hazard ratio for congenital abnormalities in children of fathers with UC was 1.30, with a confidence interval (0.92 to 1.85) that crosses no effect (Nørgård 2022).
• Thiopurines. This is a good example of evidence changing. A single-centre US study published in 2000 reported complications in 4 of 13 pregnancies fathered by men taking mercaptopurine within 3 months of conception (Rajapakse 2000). A Danish nationwide study of 699 children fathered by men using azathioprine or mercaptopurine in the 3 months before conception, compared with over a million unexposed children, found no significant increase in congenital abnormalities (adjusted OR 0.82), preterm birth or small size for gestational age (Nørgård 2017). Thirteen pregnancies against nearly 700 is not a contest.

We did not find good evidence on methotrexate or the newer small molecules in men in the sources we read, and the consensus does not cover them. Ask specifically if you take one of those.

Will my child get ulcerative colitis?

Most children of a parent with UC never develop IBD, but their risk is several times the average, and the published absolute figures disagree with each other. The consensus suggests counselling that children with a first-degree relative with IBD have an increased risk of developing it, a conditional statement on low-quality evidence (Mahadevan 2025).

We could not reconcile the 3% and the 6% from what we read. The 6.26% does not appear in the Danish study's abstract, only in the consensus's description of it, and we could not read that paper in full. The 3% handout states that its parenthood project is funded through support from UCB, a drug company, which does not make the number wrong but is worth knowing. A plausible reading is that the figures come from different populations and different lengths of follow-up. Either way the honest summary is the same: somewhere around 94 to 97 children in 100 with one parent who has UC will not develop IBD.

Two further points from the consensus. Risk is higher when more than one first-degree relative has IBD and when IBD starts young, and children of a parent with Crohn's disease may have a higher risk than children of a parent with UC. Mother and father appear to pass on similar risk in most recent studies. There is no evidence that the mode of delivery changes IBD risk in children of mothers with IBD (Mahadevan 2025).

One Reddit thread asked whether genetic testing could help. One commenter answered that the testing they had done was not about UC at all, it found a different inherited condition entirely (r/UlcerativeColitis). None of the guidance we read describes any test that predicts whether a particular child will develop UC. Carrier screening offered in pregnancy care is a separate conversation with your obstetric team.

Contraception while you get ready

The consensus prefers long-acting reversible contraception (an IUD or implant) over oestrogen-containing methods for women with IBD who want contraception. That is consensus statement 4. The reasons it gives are that oestrogen-containing methods raise the risk of blood clots in the general population, that IBD activity, steroids, JAK inhibitors and recent surgery add to that risk, that diarrhoea and other medicines can interfere with pill absorption, and that long-acting methods are the most effective (Mahadevan 2025). It notes that a systematic review found no link between oral contraceptives and IBD flares, and that the extra-surgery signal it mentions came from Crohn's disease, not UC.

For planning, the practical point is control over timing. If your colitis is active or you are switching to or from a medicine that should not be taken around conception, reliable contraception is what lets you choose when the 3 to 6 months of documented remission starts counting.

Vaccines, nutrition and the rest of the checklist

The consensus preconception checklist goes beyond the colon. Its Table 5 lists (Mahadevan 2025):

• Stopping smoking and other substances, including alcohol, recreational drugs, opioids and cannabis. If you are an ex-smoker with UC and worried about quitting, the evidence on that is in does smoking help ulcerative colitis, and for drinking see alcohol and UC flares. One Reddit poster described flaring after stopping cannabis as soon as they found out they were pregnant, which is a reason to plan that change before conception rather than at the positive test (r/UlcerativeColitis).
• Folic acid, in a prenatal vitamin started at least a month before conception. The consensus advises a higher dose for people taking sulfasalazine and for some others, such as those with malabsorption or a family history of neural tube defects. Your doctor will tell you which applies.
• A nutritional assessment. Iron, vitamin B12, vitamin D and folate deficiencies are the most common in IBD, and the consensus recommends checking them before conception or early in pregnancy. Iron deficiency in particular is common in UC and takes time to correct; UC fatigue and low iron covers what ferritin and the other numbers mean.
• Weight. Aim for a healthy range and record a baseline, so weight gain in pregnancy can be tracked against it.
• Vaccinations and cervical screening up to date. The list names annual flu, hepatitis B, MMR and varicella. MMR and varicella are live vaccines, avoided if you take high-dose steroids, thiopurines or biologics, and should be given at least 28 days before pregnancy. If you need them and are about to start one of those medicines, the order matters.
• Specialist review where relevant: maternal-fetal medicine, and a colorectal surgeon if you have had pouch surgery.
• Communicating your IBD plan to everyone else involved in your care.
• Regular physical activity.

Who should be on your team

At minimum, your IBD team before conception and an obstetric team that talks to them during pregnancy. Ideally, a maternal-fetal medicine specialist as well. The consensus says all pregnancies in women with IBD should be considered high risk for complications (Mahadevan 2025). The AGA's patient handout goes further, saying pregnant women with IBD should coordinate care with a maternal-fetal medicine (MFM) subspecialist and be followed by a gastroenterologist with IBD expertise, while acknowledging not everyone has access to that (AGA 2023).

The thread that seeded this article planned to talk to a primary care doctor first, then a gastroenterologist, then an obstetrician. Replies suggested putting the gastroenterologist first, since a primary care doctor may not know IBD medicines in pregnancy and an obstetrician may not know UC, and several people strongly recommended seeing an MFM specialist (r/UlcerativeColitis). That matches the consensus, which puts the IBD provider at the centre of preconception counselling. If you need help with what to raise, questions to ask a gastroenterologist about colitis has a starting list, and the preconception questions in this article can be added to it.

A useful question to ask at that appointment: "If I flare after we start trying, or early in pregnancy, what is the plan, and who do I call?" Several people in the threads described their gastroenterologist giving them a rescue plan in advance, which saves days of uncertainty if it is needed.

What to track in the months before you try

A simple, steady record of the months before conception gives your team the evidence they need to say "documented remission", and gives you a baseline to compare against once pregnancy changes your bowels. Pregnancy itself alters stool pattern, energy and blood counts, so knowing your normal in advance makes later changes easier to interpret. The IBD symptom diary guide covers the fields in detail. For preconception planning, the useful items are:

• Daily stool frequency, any blood, and urgency, so you can show a stretch of quiet weeks rather than describe them from memory. How to know if your UC is flaring explains how those signals are scored.
• Every calprotectin and CRP result, with the date. The consensus target is calprotectin below 150 with a normal CRP, and a run of results is more convincing than a single one.
• Medication taken, and any missed doses. Adherence is one of the things preconception care improves, and it is easier to discuss with a record.
• Steroid courses, with start and stop dates, since the target is steroid-free remission.
• Your cycle, if you are the one trying to conceive, since flares and steroids can disrupt it.

If you use an app for this, Clairop can produce a one-page GI visit report with an activity score, bowel pattern, medication adherence and labs to take to your preconception appointment (how Clairop works). A notebook works too. What matters is that the record exists before the appointment, not that it is digital.

The hard cases

Not everyone gets a tidy three to six months of remission, and the consensus acknowledges that. Some situations people describe:

Your disease will not settle. In one thread, a person who had failed two biologics, had two miscarriages and still had a calprotectin of 491 wrote that pregnancy felt unreachable (r/UlcerativeColitis). The consensus position for this situation is to optimise control as far as realistically possible rather than wait indefinitely, especially as maternal age rises. Options people raised included other drug classes, IVF timed to the best window, and surgery. For some people with refractory UC, colectomy is a route back to a pregnancy free of active colitis, at the cost of the fertility effects described above. Life after colectomy for UC is a realistic look at that path.

You get pregnant before you planned. This happens, and it is not a reason to panic or to stop medicines. Tell your IBD team promptly. Our pregnancy flare article has a section for exactly this.

You flare after getting the go-ahead. That is the situation in the "trying to get pregnant" thread above. The consensus answer is the same as at any other time: get the flare treated, re-establish remission, and restart the clock, ideally with a plan that keeps you on pregnancy-compatible medicines so switching is not needed.

You were diagnosed during or just after a pregnancy. Several people in the threads were diagnosed during pregnancy. Planning a next pregnancy then starts from the same checklist, with the extra information of how the last one went: activity during a previous pregnancy predicted flares in the next in the Danish cohort (Vestergaard 2023).

Breastfeeding questions come up quickly once a baby is on the way. The consensus recommends breastfeeding and says it is not associated with an increased risk of flares, with a list of which medicines are compatible; our article on breastfeeding with ulcerative colitis goes through it.

Myths about planning a pregnancy with UC

"You can't get pregnant with UC." Women with medically treated UC have fertility close to that of women without it, averaging 1.59 children against 1.62 in matched women in Sweden (Druvefors 2021).

"Stop your medicines before you start trying." For most maintenance medicines, the consensus recommends or suggests continuing them. Methotrexate and the small-molecule drugs are the exceptions, and even then the decision is made with your team (Mahadevan 2025).

"Pregnancy will put my UC into remission, so I can try now." Some people do feel better in pregnancy, and the threads have plenty of those stories. But activity around conception strongly predicts activity during pregnancy (Vestergaard 2023), and for UC specifically the trend is towards more relapse rather than less, as our flare-in-pregnancy article explains.

"Feeling fine means I'm in remission." The consensus asks for objective confirmation, because symptoms and inflammation do not always match.

"My child will get UC." Most will not. The risk is raised but, in absolute terms, small.

"Men with UC need to stop all their medicines before conceiving." The evidence for mesalamine and thiopurines in fathers is reassuring (Nørgård 2022; Nørgård 2017). Sulfasalazine reduces sperm quality, reversibly (O'Moráin 1984).

"If I've had a j-pouch I can't have children." Fertility is lower after a pouch, but many people conceive, and IVF after a working pouch appears to succeed at rates similar to medically treated UC (Laube 2021).

When to see a doctor promptly

While you are planning, these need a call to your IBD team or a doctor promptly rather than waiting for the next scheduled appointment:

• Blood in your stool that is new, increasing or not settling, or a return of urgency and frequency after a period of remission.
• Unexplained weight loss, fever, or symptoms waking you at night.
• Signs of anaemia: breathlessness on exertion, a racing heart, dizziness or marked tiredness.
• A positive pregnancy test, especially if you are on methotrexate or one of the small-molecule drugs. Do not stop anything first; call.
• Severe abdominal pain, a swollen abdomen, or frequent bloody stools with feeling generally unwell, which needs same-day assessment. When to go to the hospital for a UC flare sets out the thresholds.
• Leg swelling or pain, chest pain or sudden breathlessness, particularly if you are on an oestrogen-containing contraceptive, a JAK inhibitor or steroids, or have had recent surgery.
• Low mood or anxiety that is getting in the way of daily life. Planning a pregnancy with a chronic illness is hard, and the Australian education study found anxiety and depression scores improved when women got clear information (Flanagan 2021).

The honest bottom line

Planning a pregnancy with UC is mostly about the colitis, not the baby. The evidence is consistent that inflammation around conception predicts inflammation during pregnancy, that inflammation is what lowers fertility, and that most maintenance medicines are better continued than stopped. The 2025 global consensus turns that into a checklist: documented, steroid-free remission for 3 to 6 months, a medicine plan agreed ahead, folic acid, vaccinations, a nutritional check, and a team that knows your plans.

What the evidence cannot do is guarantee a calm pregnancy, and much of it is rated low or very low quality by the consensus itself. The best preconception study was not randomised, the absolute numbers for heredity disagree, and some reassuring statements are expert opinion. Planning does not remove uncertainty. It moves the decisions you can control to the months when you have the most time to make them well.

If you only do one thing after reading this, tell your gastroenterologist you are thinking about pregnancy, even if it is a year or more away. Everything else on the list starts from that conversation.