Management of Multiple Pregnancy Donald School Journal of Ultrasound in Obstetrics and Gynecology, July-September 2009;3(3):45-49 45 Management of Multiple Pregnancy Joachim W Dudenhausen Klinik für Geburtsmedizin, Charité – Universitätsmedizin Berlin, Berlin, Germany Correspondence: Joachim W Dudenhausen, Klinik für Geburtsmedizin, Charité – Universitätsmedizin Berlin, Campus Virchow- Klinikum, Augustenburger Platz 1, D-13353, Berlin, Germany, e-mail: Joachim.Dudenhausen@charite.de REVIEW ARTICLE Abstract Background: Changing delivery age and successes in reproductive have medicine induced an increase in incidence of the multiples in the industrialized world. Methods: Selective literature research was performed complemented by the autor’s clinical experience and national and international guidelines. Results: The risks of prematurity, IUGR, and antenatal demise are raised. Maternal risks are pre-eclampsia, diabetes, and bleeding during delivery. Prenatal and genetic diagnostics including ultrasonography are the most important methods of supervision during pregnancy. These are significant for diagnosis of twin-to-twin transfusion syndrome and cygosity. Consequences: Cooperation betweeen prenatal medicine, obstetrics and neonatology is important for the care of mothers with multiples. Keywords: Multiples, prematurity, IUGR, ultrasound. FREQUENCY The frequency at which multiple gestations occur varies considerably from country-to-country. The rule established in 1895 by Hellin to assess the frequency of multiple pregnancies essentially continues in force even today: if twins are born at a frequency of 1:85, triplets will be born at a frequency of 1:85 × 85 and quadruplets at a rate of 1:85 × 85 × 85. These rates are considerably higher in early pregnancy. Boklage followed 325 twin pregnancies, of which 19% ended on the due date with twins being born, 39% were, singleton births, and in 43% of the cases, no live child was born. He calculated the likely conception rate for twins as being 1:8. 7 In most European countries, the rate of twin births decreased in the 1960s from about 12 per 1,000 pregnancies to around 9.5, subsequently increasing again from the early 1980s onwards to about 12 per 1,000 pregnancies, and reaching 13 to 14 twin births per 1,000 pregnancies around 1990. The development apparent in the course of the 1960s and 1970s was primarily caused by changes in the age structure of pregnant women (initially, the numbers of younger pregnant women increased, later followed by an increase of pregnant women over the age of 35). The increased rate of multiple pregnancies following 1990 is generally perceived to be a result of the efforts of reproductive medicine. The increased frequency of high-order multiple pregnancies since the late 1980s can only be termed dramatic. In the old federal States of the Federal Republic of Germany, the rate of triplets increased between 1975 and 1990 by about 170%; in the Netherlands, it did so at a rate of 300%. Generally, induced ovulation and IVF are regarded to be the causes at the root of this development. Where, the frequency of dizygotic twins is concerned, the occurrence of multiple pregnancies in the mother’s family has considerably greater impact than the instance of multiples in the father’s family does. About 2% of the women who themselves were a dizygotic twin gave birth to twins. By contrast, the frequency of twins being born by women whose husbands were dizygotic twins was only around 1%. 5,6 ADAPTION OF THE MOTHERS TO THEIR MULTIPLE PREGNANCIES As a general rule, the mothers’ organisms will undergo greater physiological changes in multiple pregnancies than in singleton pregnancies. Thus, the circulating blood volume will increase by 25 to 30% at its peak in the 32nd through 36th week of pregnancy, whereas, this increase will amount to 50 to 60% in a twin pregnancy. In other words, a twin pregnancy will entail an additional volume of 500 ml of blood over the increased blood volume occurring in a DSJUOG