The current study determined the proportion of young women from rural areas who utilize optimum ANC and PNC services. The current study showed that about 75% of young women in rural zone in the eastern of Tigray (Northern Ethiopia) have an optimum utilization of ANC while it is lower for optimum utilization of PNC (16%). Older age and knowing the availability of AYFHS were observed to be positively associated with higher likelihood of optimum ANC use. Furthermore, optimum PNC use was observed to be increased in those women that know the availability of AYFHS and in those that have the right to make self-decision for health care spending.
The observed magnitude of optimum ANC utilization is close to what it was observed in a national Ethiopian survey (77.7%) , but significantly higher than what was found in other low-income countries, such as Nigeria (45–56%) [6, 36], Bangladesh (30%) , Côte d’Ivoire (60.2%) , and Democratic Republic of Congo (41.2%) . A proper ANC service utilization is strongly related to higher opportunity to detect and manage adverse pregnancy outcomes, including mothers’ death . In Ethiopia, maternal mortality ratio is high, accounting for 401 maternal deaths per 100,000 live births , that is about 50 times higher than in high-income countries. These factors suggest that major effort should be done in order to increase the level of adherence to the optimum ANC service utilization to reduce maternal mortality.
Results from this study suggested that older young women (20–24 years old) have an increased probability to receive optimum ANC than younger mothers (18–19 years old). Several other studies observed similar results [30, 41], even if there is still debate on it . Among other explanations, pregnancies in younger women are more probably unwanted  and there is a clear association between unintended pregnancies and a reduced health seeking behavior[43, 44].
As regarding PNC, only 16% of young women were observed to have an optimum utilization. This extremely low utilization is almost the same with national average of the country [45, 46], and Myanmar (19%) , and even higher than the study results from Nigeria (7.8%). Absent or reduced PNC service utilization was observed to be associated with an increase of neonatal death both in the first week and in the first month in Sub-Saharan Africa . Moreover, an increased maternity services utilization was found to be associated to several health outcomes of the newborns, including greater attendance of underweight infants at child welfare clinics  and a better control for HIV (Human Immunodeficiency Virus) possible infection in children of HIV infected mothers . PNC services utilization has been demonstrated to be associated with higher uptake of postpartum modern contraceptives, reducing unintended pregnancies and providing adequate child spacing in between births, all elements that increase women reproductive health care .
Results from our study indicated high drop out in the continuum of maternal and newborn care. This high dropout could be explained by different reasons like: cultural barriers [13, 50–52], dissatisfaction from previous service , and autonomy to receive health service . A possible further explanation for the low use of PNC might be also due to low level of awareness about the importance of the service even when there are no complications after birth [6, 10, 13, 28, 31, 46].
Interestingly, in our study, optimum PNC service utilization was associated with self-decision making for health care spending. Though PNC is free service in Ethiopia, is probably related with the general autonomy of the young women  and with the indirect costs, like transport cost.
Finally, knowing the availability of AYFHS around the dwelling area was a significant determinant for optimum use of both ANC and PNC services, consistently with what was already found in literatures [52, 53]. This information is important for public health implications, suggesting the importance of AYFHS development and communication interventions.
Strength and limitation
There are several limitations of the study that should be taken into account. First, it is cross-sectional design does not allow to infer causality. Second, data are self-reported and this could lead to misclassification or to recall-bias. Finally, it was not studied the relation between optimal ANC and PNC utilization and mother or child health outcome. Despite these limitations, this study is important as it gives a clue on how women in a rural African are utilizing ANC and PNC services in the continuum of care, using standardized methods for collecting data in a representative sample of Tigray women with a high rate of response and participation.