News Highlights

• Oral contraceptive pills that contain drospirenone do not have a higher risk of cardiovascular events than pills that contain levonorgestrel
• Baseline risk of venous thromboembolism likely higher than previously reported

Ask sexualityandu.ca

• I am using Nuva Ring® for contraception.  Can it get lost inside of me?
• Can you explain how the birth control pill works to help acne?
• Is HPV curable?

Tips

• There are two methods of the “morning after pill” available for use in Canada

Quick facts

• OC use not likely to increase symptoms of depression

Did you know?

• One half of men who tried a new male hormonal contraception method found it to be acceptable

Oral contraceptive pills that contain drospirenone do not have a higher risk of cardiovascular events than pills that contain levonorgestrel. 

It is known that the use of combined hormonal contraception in young women and hormone replacement therapy in menopausal women increase the risk of a blood clot (venous thromboembolism, VTE).  This risk is mainly attributed to the estrogen in the pills, but there has been ongoing controversy about whether or not different progestins influence these rates.  Current users of levonorgestrel-containing oral contraceptives appear to have the lowest rates of VTE; however, this may be due to the fact that cases in levonorgestrel users are under reported while cases in other products are over reported.

A recent international study followed women who were starting an oral contraceptive pill (OC) and monitored them for cardiovascular events, including VTEs.  Specifically, the researchers looked at the risk of VTE with a new drospirenone-containing oral contraceptive pill (Yasmin®) in comparison to levonorgestrel-containing pills and other pills marketed in Europe.  This surveillance program, which is the first of its kind, was funded by Bayer-Schering Pharma.

Overall, 58,674 women were followed for a total of 142,475 women-years.  They were divided in five categories: drospirenone OC users, levonorgestrel OC users, other OC, non-oral hormonal contraceptive users (such as the contraceptive patch), and non-users of hormonal contraception.  Women filled out questionnaires every six months.  Statistical analysis was by both “intention to treat” and “as treated” when calculating the rates of adverse events.  The groups were generally the same, although the drospirenone group were more obese and had a higher baseline rate of arrhythmia (irregular heart beat). Impressively, only 2.4% of women were lost to follow up.

When the drospirenone group was compared with the levonorgestrel group, there was no difference in the rates of VTE, stroke, heart attack, arrhythmia or death.  The risk of a blood clot in obese women (BMI > 30) was 3 times higher than the risk in non-obese women (BMI < 25).  Most blood clots occurred within the first three months of use.  This large, well designed and well conducted study shows that VTE rates are comparable for all different progestins in combined oral contraceptives. In particular, the drospirenone-containing pills were not more likely to cause VTE than levonorgestrel-containing OCs or other third generation OCs.

Dinger J, Heinemann L, Kuhl-Habich D.  The safety of a drospirenone-containing oral contraceptive: final results from the European Active Surveillance study on Oral Contraceptives based on 142,475 women-years of observation.  Contraception May 2007.  Advance publication on-line.

Baseline risk of venous thromboembolism likely higher than previously reported

Contraceptive methods that contain both estrogen and progestin increase the chance of having a venous thromboembolism (VTE).  However, it has been difficult to establish the level of increased risk because the risk in the general population is uncertain.  Until now, the generally accepted baseline risk of VTE for a women under age 50 was believed to be approximately 1/10,000 women per year.  However, some studies have reported rates higher than this.  Accurate information on this risk is important for counseling women in a variety of circumstances, including when they are considering hormonal contraception.

A German research group reviewed available medical literature on the incidence of VTE, including deep vein thrombosis (DVT) and pulmonary embolism (PE).  There were wide variations in rates depending on the age and methodology of the study.  The main study types were: community based (looking at VTEs in a specific community); cohort studies (following a group of people over time to see how many clots developed); and database studies (information gathered for administrative use, not necessarily research). 

The risk from the community studies ranged between 5-16/10,000 women per year, the cohort studies ranged from 5-10/10,000 women per year, and the database studies ranged from 0.7-3.6/10,000 women per year.  These differences were likely due to differences in study design, data collection, and definition of the diagnosis of VTE.

The authors concluded that the more likely baseline VTE rate in reproductive aged women is 5-10/10,000 women per year. 

Heinemann L, Dinger J.  Range of published estimates of venous thromboembolism incidence in young women.  Contraception, May 2007.  Advance publication on line.

I am using Nuva Ring® for contraception.  Can it get lost inside of me?

No.  The vagina is a blind-ended tube, kind of like a sock.  At the top is the cervix and uterus, and the bottom is the opening to the outside.  As a result, there is nowhere for the ring to go.  Once it is inserted, it just sits in the vagina.  Like a tampon, if it is in the right spot, you can’t feel it.  If you can feel it, it is not in far enough.  Just push it up with your finger until you cannot feel it anymore.  When it comes to taking it out, just reach into the vagina with your finger and hook the edge of the ring.  It will pull out easily.

Can you explain how the birth control pill works to help acne?

Estrogen in the pill raises the level of a protein in the blood called Sex Hormone Binding Globulin, or SHBG for short.  This protein binds to androgens (male hormones) and lowers the amount of them that can get to the skin surface where they would normally lead to oil secretion and acne.  The second hormone in the pill, progestin, suppresses production of androgens from the ovary. So the pill has two ways that it can reduce acne and oily skin. Some new pills have special progestins that actually block the effects of androgens as well. Your doctor may recommend these pills if you have persistent acne or increased facial hair growth.

Is HPV curable?

Yes and no.  Most of the time, your body will get rid of an HPV infection like it gets rid of a cold virus.  It can take up to two years to do this.  However, some types of HPV are harder to get rid of, and can cause genital warts or pre-cancerous lesions of the cervix.  There is a new vaccine available for HPV.  Talk to your health care provider to see if you are a candidate.  It does not cure an infection that is already there, but can lower the chance you will get a new infection of HPV. For more information, visit www.hpvinfo.ca

One half of men who tried a new male hormonal contraception method found it to be acceptable.

A research group from the State of Washington tested 38 healthy men with a combination of Depo Provera injections every three months and Testosterone gel applied daily to the skin.  This combination of drugs suppresses sperm production in up to 90% of men who use it.  This research study was performed to determine men’s acceptance of the contraceptive method. 

The men used the method for a total of 24 weeks, and filled out questionnaires before, during, and after the trial.  Fifty percent of the men studied found the method acceptable and 45% would use it if it were available commercially.  The majority found the skin gel easy to use, but 1/3 found it interfered with their daily routine.  Sexual function remained unchanged throughout the study, but some men found a slight decrease in sexual function once they stopped using the gel.

Amory JK, Page ST, Anawalt BD, Matsumoto AM, Bremner WJ. Acceptability of a combination testosterone gel and depomedroxyprogesterone acetate male contraceptive regimen.  Contraception. 2007 Mar;75(3):218-23

OC use not likely to increase symptoms of depression.

Researchers in Australia reviewed the data from a large national survey of women to determine if there was a link between OC use and depression.  The Australian Longitudinal Study on Women’s Health is following three groups of women over 20 years.  The youngest group of women, who started the study aged 18-23, was the focus of this report.  The first survey was done in 1996, with part 2 in 2000 and part 3 in 2003.  Of 9,688 women who completed part 2 of the survey, and 9,081 women who completed part 3 of the survey, 5342 and 4202 were using oral contraception at the time of the survey, respectively.

Compared to women not using oral contraception, women using OCs for the main purpose of pregnancy prevention did not have an increased rate of depressive symptoms.  Women who were using OCs for other reasons (eg: heavy periods, pelvic pain, endometriosis) were 1.3 times more likely to have depressive symptoms than women using the pill for contraception only.  Interestingly, the longer a woman used the OC, the lower her chances of having symptoms of depression.  The researchers were uncertain as to the cause of the increased depression symptoms in women using the pill for other reasons.

Duke JM, Sibbritt DW, Young AF.  Is there an association between the use of oral contraception and depressive symptoms in young Australian women?  Contraception. 2007 Jan;75(1):27-31

There are two methods of the “morning after pill” available for use in Canada. 

The original method, also known as the Yuzpe method, uses a total of four tablets of the birth control pill Ovral (two tablets taken immediately and again 12 hours later).  This is two doses of 100 mcg of ethinyl estradiol and 500 mcg of levonorgestrel.  A doctor’s prescription is required for this method. 

The second method, known as Plan B®, is two pills containing 750 mcg of levonorgestrel, taken 12 hours apart.  Some women find it easier to take both of the pills in Plan B® at the same time instead of 12 hours apart; it is just as effective if taken this way.  Plan B® is now available from pharmacists without a prescription.

In a pinch, other birth control pills can be used to make up the equivalent dose of the Yuzpe method.  Alesse® (two doses of 5 pills each), Triphasil® (two doses of 4 yellow pills each), Triquilar® (two doses of 4 yellow pills each), or Min Ovral® (two doses of 4 pills each) have an equivalent success rate to the Yuzpe method. 

Canadian contraception consensus.  J Obstet Gynaecol Can. 2004 Feb;26(2):143-56