Progesterone Use in Non-Obstetric Surgery During Pregnancy
Progesterone should be continued during non-obstetric surgery in pregnant patients who are already receiving it for established indications (prior spontaneous preterm birth or short cervix), but should not be initiated solely because of planned surgery. 1
Current Evidence Base
The evidence for progesterone use specifically during non-obstetric surgery in pregnancy is extremely limited. One review mentions that progesterone is "used in pregnant women undergoing nonobstetric surgery" as a clinical practice, but provides no randomized trial data, dosing recommendations, or outcome evidence for this specific indication. 1 This represents expert opinion rather than evidence-based guidance.
Clinical Decision Algorithm
For patients ALREADY on progesterone therapy:
Continue existing progesterone regimens through the perioperative period based on the following rationale:
If receiving 17-alpha-hydroxyprogesterone caproate (17P) 250 mg IM weekly for prior spontaneous preterm birth: Continue weekly injections without interruption, as this therapy has demonstrated a 34% reduction in recurrent preterm birth and should not be discontinued. 2, 3
If receiving vaginal progesterone (90 mg gel or 200 mg suppository daily) for short cervical length ≤20 mm: Continue daily administration, as this reduces preterm birth before 33 weeks and composite neonatal morbidity/mortality. 2, 3
For patients NOT currently on progesterone:
Do not initiate progesterone solely for non-obstetric surgery, as there is no evidence supporting this practice. 1
The only established indications for progesterone in pregnancy are:
- Singleton pregnancy with prior spontaneous preterm birth at 20-36 weeks (use 17P 250 mg IM weekly starting 16-20 weeks until 36 weeks) 2, 3
- Singleton pregnancy with cervical length ≤20 mm at 18-24 weeks without prior preterm birth (use vaginal progesterone 90 mg gel or 200 mg suppository daily until 36 weeks) 2, 3
Critical Populations Where Progesterone Has NO Benefit
Avoid initiating progesterone in these scenarios even if surgery is planned:
- Multiple gestations (twins, triplets) regardless of surgical indication 3, 4
- Active preterm labor 3, 4
- Preterm premature rupture of membranes (PPROM) 2, 3
- Singleton pregnancies without risk factors (no prior preterm birth and normal cervical length) 3, 4
Perioperative Considerations
Timing and administration:
- Vaginal progesterone capsules cause transient dizziness and drowsiness, so timing around anesthesia should be considered, though continuation is still recommended. 5
- IM 17P injections can be administered on schedule regardless of surgical timing. 2
- If the patient has been receiving 17P for prior spontaneous preterm birth and develops complications (such as PPROM), it is reasonable to continue 17P in the absence of evidence to the contrary. 2
Route-specific issues:
- Oral contraceptives and potentially oral medications may have altered absorption after bariatric surgery due to anatomical changes, but this does not apply to IM or vaginal progesterone routes used for preterm birth prevention. 2
Common Pitfalls to Avoid
Do not substitute vaginal progesterone for 17P in women with prior spontaneous preterm birth, as direct comparison trials show 17P is superior for this specific indication. 3 The formulations are not interchangeable. 3
Do not use progesterone as a tocolytic agent perioperatively if preterm contractions develop, as there is insufficient evidence for progesterone as primary, adjunctive, or maintenance tocolysis. 2
Do not discontinue established progesterone therapy out of concern for surgical complications, as the FDA labeling notes progesterone may cause fluid retention requiring careful observation in cardiac or renal dysfunction, but does not contraindicate continuation. 5