Postpartum visit attendance after spontaneous and medically indicated preterm birth

Individuals with preterm birth (PTB) are less likely to attend postpartum visits compared to those with term birth but are more likely to have conditions such as hypertensive disorders. PTB can be classified as spontaneous PTB (sPTB) (premature rupture of membranes or preterm labor) and medically indicated PTB (mPTB) (clinician-initiated due to maternal or fetal conditions). We compared postpartum visit attendance after sPTB and mPTB to term birth. We hypothesized that sPTB and mPTB would be associated with increased risk of not attending postpartum visits compared to term, but risk would be higher after sPTB as mPTB is more often preceded by chronic conditions requiring more healthcare engagement.

We performed a retrospective cohort study of births from 2008 to 2019 in GeoBirth, a curated dataset of singleton births in two hospitals in Philadelphia, PA. Two blinded reviewers manually classified each PTB as sPTB or mPTB. We performed bivariate analyses and mixed-effects, multivariable, modified Poisson regression models to calculate risk ratios (RRs) of no postpartum visit after sPTB and mPTB compared to term birth. Models were adjusted for age, parity, hospital, insurance, education, race and ethnicity, cesarean birth, body mass index, diabetes, and hypertension. A linear combination test compared RRs between PTB subtypes.

Of the 69,110 included births, 3464 (5.0%) were sPTB and 2755 (4.0%) were mPTB. There were 693 (1.0%) excluded as unclassifiable PTBs. Overall, 37.2% of births had no postpartum visit within 12 weeks, with higher proportions after sPTB (46.5%) and mPTB (42.8%) than term birth (36.4%) (p < 0.001). Compared to term birth, the unadjusted risk of no postpartum care was higher after sPTB (RR, 1.28; 95% confidence interval [CI], 1.23-1.33) than mPTB (RR, 1.18; 95% CI, 1.12-1.23) (p value comparing RRs = 0.004). In a model including all covariates, risk was similarly elevated for both sPTB (aRR, 1.14; 95% CI, 1.11-1.19) and mPTB (aRR, 1.15; 95% CI, 1.10-1.21) (p value comparing RRs = 0.78).

Individuals with both sPTB and mPTB are at higher risk of not attending postpartum visits compared to term births. Innovative, collaborative, multidisciplinary efforts are essential to meet the needs of this vulnerable population to ensure postpartum healthcare.