Are Vaginal Examinations in L&D an Infection Risk?

For most L&D nurses, vaginal examinations have almost become routine procedure and are often performed without much forethought for negative consequences.

Although a quick vaginal exam can deliver an abundance of information in terms of cervical effacement, dilatation, membrane integrity and fetal position and station, it is inherently an invasive procedure that may be risky in certain situations. Furthermore, research has shown that the performance of multiple vaginal examinations can be a risk factor for maternal or fetal infection. The authors of a term prolonged rupture of membranes (PROM) study point out that the number of vaginal examinations is more predictive of maternal infection than duration of membrane rupture (Seaward, PG et al, 1997). Maternal infection may occur during labor (chorioamnionitis) or after birth (postpartum endometritis), and prolonged rupture of membranes and multiple vaginal examinations are known risk factors for the development of maternal and neonatal infection. However, infection can also be an etiologic factor that causes pre-labor rupture of membranes (Marowitz, A, 2004).
Other factors that are also known to increase risk of infection in term pregnancies are maternal group B streptococcus status, use of internal monitoring, mode of delivery, presence of meconium in the amniotic fluid and time between rupture of membranes and delivery (Seaward, PG et al, 1997).

In addition to avoiding the excessive use of vaginal exams with PROM, vaginal examinations should be completely avoided in any high risk delivery or a labor with a history of vaginal bleeding. In these circumstances, the nurse should never perform a vaginal or rectal examination or take any action that would further stimulate uterine activity. Performing a digital examination can cause severe bleeding and compromise fetal status further. High risk deliveries include placental anomaly (such as Placenta Previa, where the placenta partially or fully covers the cervical os) and Premature labors (less than 38 week gestation).

In the case of an Abruptio Placenta (premature detachment of the placenta from the uterine wall prior to delivery), two sterile gloved fingers should be immediately inserted into the vagina to lift the presenting part off of the umbilical cord to relieve cord compression. Prompt recognition and management of a prolapsed cord is important to prevent fetal hypoxia from prolonged cord compression.
In caring for women with ruptured membranes, there may be considerable pressure to intervene in an attempt to prevent infection and little support for avoiding interventions known to contribute to the risk. However, interventions such as frequent vaginal examinations and internal monitoring may actually increase the risk of infection and do more harm than good.

Limiting vaginal examinations cannot be overemphasized. Women with pre-labor rupture of membranes should not receive vaginal examinations until after labor begins and then only when the results are necessary to guide or alter management.

Almost 40 years ago, Shubeck et al. wrote that the clock of infection begins ticking with rupture of membranes (Marowitz, A, 2004). We have since learnt that not only was he correct in his hypothesis, but he had also foreseen the connection between infection and PROM. Today we know that the causes of infection are complex and inter-related. Although many questions regarding ruptured membranes, vaginal examinations and infection risk remain unanswered, one concept is clearly identified: avoid vaginal examinations whenever possible.