Meta-analysis topic ideas in obstetrics and gynaecology

Obstetric research is shaped by a simple fact: pregnant women have been excluded from most drug trials, so a large share of what is known about medicines in pregnancy comes from observational studies, registries and small trials. Gynaecology has the opposite pattern, with many device and surgical trials in conditions such as endometriosis and fibroids.

Outcomes come in pairs: a maternal outcome and a neonatal one, often over different time spans. Choosing which you pool, and writing down the definitions of preterm birth, small for gestational age and hypertensive disorders, is the heart of the work.

Find a obstetrics and gynaecology topic that has not been done

SynthGap searches the published literature, checks each candidate against existing systematic reviews, and proposes topics with the primary studies behind them. Start on the Free plan: no card needed, and every run shows every topic it finds.

Where gaps tend to hide in obstetrics and gynaecology

Medicines and pregnancy

The safety of commonly used drugs in pregnancy is assessed in observational studies with confounding by indication. Reviews that separate drug, trimester and outcome, and that take account of the underlying illness, are scarce for many drugs.

Prevention of pregnancy complications

Aspirin and calcium for pre-eclampsia, progesterone for preterm birth, and lifestyle and exercise interventions are studied in trials with different risk groups and doses.

Labour and birth

Induction methods, timing, analgesia and perineal care have many trials with outcomes defined differently.

Gynaecological conditions

Endometriosis, polycystic ovary syndrome, fibroids and heavy menstrual bleeding have trials of drugs, devices and surgery with patient-reported outcomes.

Fertility and assisted reproduction

Add-on treatments in IVF are studied in small trials where live birth, clinical pregnancy and ongoing pregnancy are different outcomes.

Outcomes and effect measures that pool well in obstetrics and gynaecology

Live birth rate per woman randomized (not per cycle or per embryo transfer): risk ratio or odds ratio. Trials often report different denominators, so check them.
Preterm birth before 37 or before 34 weeks: risk ratios, with the gestational age cut-off reported.
Pre-eclampsia, gestational diabetes and postpartum haemorrhage: risk ratios, with the diagnostic criteria stated, since they changed over time.
Birth weight and small for gestational age: mean differences or risk ratios, with the reference chart defined.
Pain and quality-of-life scores in gynaecological conditions: standardized mean differences, with the follow-up point planned in advance.

Common traps in obstetrics and gynaecology reviews

Using different denominators for pregnancy outcomes (per cycle, per transfer, per woman) in one pooled estimate.
Pooling twin and singleton pregnancies without separating them.
Ignoring that diagnostic criteria for pre-eclampsia and gestational diabetes changed between older and newer trials.
Confounding by indication in observational drug safety studies in pregnancy.
Counting multiple publications from one IVF trial as separate studies.

Check before you commit

Before committing months to a topic, check that nobody has beaten you to it. Search PubMed with its systematic review filter, the Cochrane Library, the PROSPERO register (for reviews that are registered but not yet published) and Epistemonikos. Look at how recent the latest review is and whether new trials have appeared since its search date. Step-by-step guide.

Starting points to try in SynthGap

These are areas to explore, not claims that they are open. Some may already be well covered, and finding that out quickly is the point.

Exercise during pregnancy and the risk of gestational diabetes and hypertensive disorders
Non-drug and drug treatments for pain in endometriosis
Antenatal corticosteroids in late preterm and term caesarean birth: neonatal outcomes

Questions

How do I check whether an obstetric meta-analysis already exists?

Search PubMed with the systematic review filter, the Cochrane Library (Cochrane Pregnancy and Childbirth, and Cochrane Gynaecology and Fertility), PROSPERO and Epistemonikos.

Can I pool trials of different fertility add-ons?

Not as one intervention. Pool by add-on, and be careful about the denominator of the live birth outcome.

Should I include observational studies of drug safety in pregnancy?

Often you must, because trials are scarce. Pool adjusted estimates where possible, separate drug exposures by trimester, and describe how confounding by the underlying illness was handled.

Other specialties

This page is general methodological guidance, not medical advice, and it does not list specific unreviewed topics. SynthGap's suggestions are AI-generated from the published literature, so verify them before registering a protocol.