Incidence and outcomes of adolescent pregnancy in consuelo, Dominican Republic between 2017-2022

Introduction

Approximately 13 % of adolescent females worldwide give birth before age 18 [1]. Adolescent mothers face elevated risks of adverse pregnancy outcomes, including preeclampsia, preterm birth, and newborn mortality, with younger adolescents (<14) at highest risk [2]. Global adolescent pregnancy rates have declined with global adolescent (age 15–19) fertility rates decreased from 92/1,000 to 39/1,000 women from 1960 to 2022. However, the fertility rate remains high in low-and-middle-income countries (LMICS, 42/1,000 in 2023) compared to upper-income countries (9/1,000) [3].

Adolescent pregnancy is a public health priority in the Dominican Republic (DR), a middle-income country [3]. While fertility rate amongst Dominican adolescents (age 15–19) decreased from 149/1,000 in 1960 to 54/1,000 women in 2022, this rate remains higher than the middle-income country average (35/1,000) [3]. From 2010 to 2015, almost one quarter (22.3 %) of DR births were to adolescent mothers (age 15–19), compared to 16.6 % in Latin America/Caribbean and 9.6 % worldwide [4]. Risk factors for adolescent pregnancy in the DR include lower household income, living in urban environments, and lower educational attainment [5], 6].

While previous studies examined Dominican attitudes towards adolescent pregnancy, there is limited research on clinical outcomes [7], 8]. To further characterize the burden of adolescent pregnancy in the DR, we determined the incidence of adolescent pregnancy in Consuelo and described maternal-neonatal outcomes.

Methods

This retrospective observational study used labor and delivery records of patients aged 10 years and older who gave birth between January 1, 2017 and December 31, 2022 at Dr. Angel Ponce Municipal Hospital in the semi-rural town of Consuelo, DR. This primary public hospital serves 60,000 people, provides free care and employs five obstetricians, equipped to perform vaginal, assisted, and cesarean section (CS) deliveries.

Each birth was characterized as an individual event. An adolescent was defined using the World Health Organization definition of age between 10 and 19 years. Adverse pregnancy outcomes included pre-eclampsia, cephalopelvic disproportion (CPD), newborn death, post-partum hemorrhage, premature birth, and low birth weight. Data were summarized using standard descriptive statistics; p<0.05 represented significance. The study was approved by institutional review boards at the Children’s Hospital of Philadelphia and in the DR, Consejo Nacional de Bioética en Salud.

Results

Of 1,292 births, 284 (22 %) were in adolescent mothers (Table 1). The rate ranged from 14 % (2022) to 27 % (2019). Vaginal deliveries were slightly more common than CS deliveries in both adolescent (75 %) and non-adolescent mothers (70 %, p>0.05). Newborns of adolescent mothers had lower median birthweight (3200 g) compared to those of non-adolescents (3300 g, p=0.003).

Regarding complications, there were overall low rates of breech (<1 %), fetal distress (2 %), and premature rupture of membranes (1 %) (Table 2). Five percent of babies had low birth weight, 6 % macrosomia, 3 % were pre-term, and 1 % post-term. The overall neonatal death rate was 1 %. In all, there was no difference between groups. However, adolescent mothers were more likely to have CPD (crude odds ratio 3.03, 95 % confidence interval 1.34–6.85, p=0.005).

Discussion

This is the first study from the Dominican Republic to use medical records to assess adolescent pregnancy rates and complications. Using data from the sole hospital serving a semi-rural town, the adolescent pregnancy rate was 22 % between 2017 and 2022. Adolescent mothers were at higher risk for CPD and their babies had slightly lower birthweights, though not clinically significant. While prior studies have focused on adolescent pregnancy on a national level, our study adds to the limited existing research focused on rural areas.

The adolescent pregnancy rate of 22 % is exactly the same as prior 2010–2015 national data [4]. While the average adolescent pregnancy rate in Latin America and the Caribbean was 15 % from 2010 to 2015, the DR was the only country with a rate>20 % [9].

Interestingly, from 2019 to 2022, the rate of adolescent pregnancy in this study decreased by almost half from 27 to 14 %. Using national Dominican data of early adolescent (age 10–14) pregnancy, Gonzalez-Rodriguez et al. found a similar decrease in the early adolescent fertility rate from 1.84/1,000 in 2019 to 1.04/1,000 in 2021 [10]. This follows a decrease over many decades in the older adolescent (age 15–19) fertility rate from 167.1/1,000 in 1960 to 93/1,000 in 2019, also noted across Latin America [11]. Initiatives by local non-profits to improve sexual education may be contributing to the decline as well as improved literacy rates and greater participation in the labor force amongst Dominican females [12], 13].

Adolescent mothers were more likely to have CPD, being mismatch between the size and/or shape of the fetal head and maternal pelvis. CPD can cause obstructed labor requiring CS [14]. Prior studies have also shown high CPD rates amongst adolescents, likely related to immaturity of the adolescent pelvic bone [15]. Despite higher CPD rates in our study, the CS rate amongst adolescents did not differ significantly from non-adolescent mothers. This may be attributed to higher rates of repeat CS coupled with overall high rates of CS in the DR, the highest among all LMICs [16].

Apart from CPD, we did not find higher rates of maternal or newborn complications amongst adolescent mothers, contrasting with other studies [2]. A case-control study using data from several hospitals across the DR found that adolescence was marginally protective against pre-term birth [17]. Together with our data, this suggests that pregnant adolescents in the DR may be benefitting from prenatal care, leading to lower complication rates.

Limitations include possible missing data, mitigated through thorough cross-checking and manual record validation. While most women in Consuelo choose to deliver in this hospital, our data does not include mothers who gave birth at other facilities or at home. While<2 % of Dominican women undergo homebirths, there is limited data on the rate amongst adolescents [18]. Due to the limited scope of medical records, we were unable to collect data on factors such as socioeconomic status or education level. Finally, this study was conducted at a single hospital in a semi-rural town, limiting generalizability. However, the study holds the advantage of describing a semi-rural community, a demographic often excluded from research.

In conclusion, while results cannot be extrapolated to the entire population, the adolescent pregnancy rate of 22 % is consistent with national surveys. Future research on larger cohorts could better characterize risk factors for adverse maternal and neonatal outcomes, which were relatively rare. Additionally, future work should examine sociodemographic factors to assess additional risk factors for adolescent pregnancy.