Maija Jakobsson

Preterm delivery after surgical treatment for cervical intraepithelial neoplasia.

OBJECTIVE: To study whether a treatment of cervical intraepithelial neoplasia (CIN) is associated with an adverse outcome in the subsequent pregnancies. METHODS: This study is a register-based retrospective cohort study from Finland. National data of 25,827 women having a surgical treatment of the cervix for CIN in 1986–2003 and their 8,210 subsequent singleton births in 1987–2004 were studied. Main outcome measures were preterm birth rate, low birth weight rate, and perinatal mortality rate. RESULTS: The risk of any preterm delivery (less than 37 weeks of gestation), especially the risk of very preterm delivery (28–31 weeks of gestation), and extremely preterm delivery (less than 28 weeks of gestation) was increased after cervical conization (relative risk [RR] 1.99, 95% confidence interval [CI] 1.81–2.20; RR 2.86, 95% CI 2.22–3.70; and RR 2.10, 95% CI 1.47–2.99, respectively). After cervical ablation, the risk of preterm delivery was also increased. The risk of low birth weight and perinatal death was increased after conization (RR 2.06, 95% CI 1.83–2.31 and RR 1.74, 95% CI 1.30–2.32, respectively). Adjusting for maternal age, parity, and maternal smoking did not affect our results. CONCLUSION: Any treatment for CIN, including loop electrosurgical excision procedure, increases the risk of preterm delivery. It is important to emphasize this when treating young women with CIN. LEVEL OF EVIDENCE: II

Loop electrosurgical excision procedure and the risk for preterm birth.

OBJECTIVE: To study whether loop electrosurgical excision procedure (LEEP) conization is associated with preterm birth and to study the effect of cone size on preterm birth. METHODS: This was a retrospective cohort study from Southern Finland conducted from 1997 to 2003, with a follow-up for subsequent births until 2006. We identified the cases from the Hospital Discharge Register and Medical Birth Register and collected additional information from the hospital records. Our cohort consisted of 624 women who delivered after LEEP conization. We calculated expected preterm birth rates by using the Medical Birth Register data. In subgroup analysis (n=258 women) we used internal controls, ie, deliveries before the treatment. The main outcome measure was preterm birth rate in different subgroups. RESULTS: The risk for preterm delivery (before 37 weeks) was increased almost threefold (relative risk [RR] 2.61, 95% confidence interval [CI] 2.02–3.20; number needed to treat for harm=14) and repeat treatments more than fivefold (RR 5.15, 95% CI 2.45–7.84; number needed to treat for harm=5) after LEEP conization compared with the background rate of preterm birth (4.61%). Large or repeat cones increased the risk twofold (RR 2.45, 95% CI 1.38–3.53) when compared with small or medium-sized cones. For women having a birth before and after LEEP conization, the preterm birth rate was 6.5% before and 12.0% after the procedure (RR 1.94, 95% CI 1.10–3.40; number needed to treat for harm=18). Adjusting for maternal age, parity, or both did not change the results. The risk for preterm birth was especially increased (RR 3.38, 95% CI 2.31–4.94) among women without previous preterm birth. CONCLUSION: Loop electrosurgical excision procedure surgery of the cervix predisposes patients to preterm birth. Loop electrosurgical excision procedure conization increased the risk for preterm birth especially among women without previous preterm birth. The rates were highest after repeat procedures. LEVEL OF EVIDENCE: II

The incidence of preterm deliveries decreases in Finland

Objective  We examined the trends and risk factors of preterm delivery.

The Nordic medical birth registers – a potential goldmine for clinical research

The Nordic medical birth registers have long been used for valuable clinical research. Their collection of data for more than four decades offers unusual possibilities for research across generations. At the same time, serum and blotting paper blood samples have been stored from most neonates. Two large cohorts (approximately 100 000 births) in Denmark and Norway have been described by questionnaires, interviews and collection of biological samples (blood, urine and milk teeth), as well as a systematic prospective follow‐up of the offspring. National patient registers provide information on preceding, underlying and present health problems of the parents and their offspring. Researchers may, with permission from the national authorities, obtain access to individualized or anonymized data from the registers and tissue‐banks. These data allow for multivariate analyses but their usefulness depends on knowledge of the specific registers and biological sample banks and on proper validation of the registers.

Abnormally invasive placenta-prevalence, risk factors and antenatal suspicion: results from a large population-based pregnancy cohort study in the Nordic countries.

The objective was to investigate prevalence, estimate risk factors, and antenatal suspicion of abnormally invasive placenta (AIP) associated with laparotomy in women in the Nordic countries.

The Nordic Obstetric Surveillance Study: a study of complete uterine rupture, abnormally invasive placenta, peripartum hysterectomy, and severe blood loss at delivery

To assess the rates and characteristics of women with complete uterine rupture, abnormally invasive placenta, peripartum hysterectomy, and severe blood loss at delivery in the Nordic countries.

Long-term mortality in women treated for cervical intraepithelial neoplasia

Objective  The objective of this study was to study whether women surgically treated for cervical intraepithelial neoplasia (CIN) have increased mortality later in life. We also wanted to study whether pregnancy beyond 22 weeks post‐treatment affects the risk.

Risk factors for blood transfusion at delivery in Finland

Objective. To examine the prevalence and risk factors for blood transfusion during delivery. Design. Register‐based retrospective cohort study from Finland. Setting. National Medical Birth Register data during 2006–2008. Sample. A total of 171 731 women having singleton deliveries, of whom 3394 (1.98%) received blood transfusion. Methods. We calculated odds ratios (ORs) with 95% confidence intervals (CIs) by multivariate logistic regression to adjust for confounders related to maternal background and mode of delivery. Main outcome measures. Blood transfusion rates by risk factors. Results. Blood transfusion rate during labor increased slightly, from 1.83% in 2006 to 2.27% in 2008 (p < 0.001), during the study period. The highest rate, almost 4%, was reported in central hospitals. Advanced maternal age and primiparity predisposed to blood transfusion. A previous cesarean section increased these rates also in subsequent vaginal delivery (2.64%) compared with women who had vaginal deliveries only (0.86%, OR 3.14, 95% CI 2.65–3.72). Induction of labor almost doubled the risk for blood transfusion (adjusted OR 1.74, 95% CI 1.60–1.89). All instrumental vaginal deliveries (adjusted OR 2.46, 95% CI 2.25–2.69) and any cesarean sections (adjusted OR 1.80, 95% CI 1.66–1.96) increased this risk. Delivery of a large‐for‐gestational age newborn increased the blood transfusion risk over twofold. Conclusions. As previous cesarean section includes an increased risk for blood transfusion, even in subsequent deliveries, it is essential to consider the mode of labor carefully. The blood transfusion rate was the highest in central hospitals, suggesting differences in blood transfusion practice.

Emergency peripartum hysterectomy: results from the prospective Nordic Obstetric Surveillance Study (NOSS)

To assess the prevalence and risk factors of emergency peripartum hysterectomy.

Treatment for cervical intraepithelial neoplasia and subsequent IVF deliveries

BACKGROUND The aim was to study whether the treatment of cervical intraepithelial neoplasia (CIN) is associated with a subsequent increase in the use of IVF to achieve deliveries and whether women with cervical treatment and IVF have increased rates of preterm delivery. METHODS This was a register-based retrospective cohort (n = 822 183 deliveries) study from Finland whose main outcome measures were the rates of IVF and preterm deliveries in different CIN treatment groups. RESULTS Of all deliveries in Finland, 1.5% (12 240) resulted from IVF treatment. This proportion was 1.6% for women who had undergone any cervical procedure [n = 150, risk ratio (RR): 1.21, confidence interval (CI): 1.04-1.42]. The risk for IVF was not increased after cervical conization, whether by loop or laser (1.6%), or ablation (1.8%). An increased number of IVF deliveries (2.7%) was observed following other excisional treatments, even when adjusted for year of delivery (RR: 1.83, CI: 1.16-2.89) or parity (RR: 1.95, CI: 1.25-3.04). Although women who had undergone any cervical procedure and IVF appeared to have an increased relative risk for preterm delivery (3.42-fold, CI: 2.18-5.37) when compared with women with neither, this was explained by maternal age and parity. CONCLUSIONS The proportion of IVF deliveries was not increased after cervical conization or ablation. This is reassuring for young women who undergo such treatments.