It could be a question that many couples will ask themselves through the years, why is my marriage so lacking in sex?  It doesn't have to be a lacking completely, but perhaps you only have sex a few times a month.  A marriage that you are having very little sex in can also be termed a sexless marriage.  So why may you as a couple be facing this situation?

Here are some of the most common causes that many couples will face to why they are having less sex then an average normal couple.

1. They simply could be on a different schedule.  There are many couples who work different times than the other one.  This can leave them either with little time alone, or just plain exhausted by the time they actually do get the time to spend with one another.
2. Kids are a big cause to a sexless marriage.  We all love kids and there is nothing wrong with having them.  But they also cut down the privacy that a couple will have and the chances that are available to spend that one on one time in the bedroom to have some sex with each other.
3. Lack of self-esteem.  This could be either partner in the relationship.  They may have gained a bit of weight or be facing some loss of hair.  The reasons are many that self-esteem could be down, but it will make them feel a lot less sexy, and not really in the mood for sex.
4. Pregnancy.  Well we all know that pregnancy can mess with a woman and how she feels.  Not only can that happen, but it could make her feel less attractive and again be something that will cause self-esteem to drop.  Again this will then lead to number 2 so it's like a vicious cycle in some cases.
5. Illness.  When one partner isn't feeling well it can put a damper on sex.  Especially if it is a long-term illness they have been suffering from.  
6. Sexual Dysfunction.  Problems with erections or other sexual dysfunction will put a quick damper on sex.  After trying a few times a couple may be more likely to simply give up and this can lead to a sexless marriage.
7. Sexual Addiction.  If one partner is addicted to sexual things, like pornography, they may not be excited about their partner.  Not only that but this problem may lead to excessive masturbation on their part.  This will then stimey their needs for sex with a partner.
8. Other Stressors.  Money or other issues in a marriage can lead to a lot of problems when it comes to sex in a marriage.  But if you communicate it is possible to work past those stressors.
9. Confusion.  One partner may have a feeling that they are homosexual.  This sexual confusion will lead to a lack of wanting to have sex with a partner of the opposite sex, thus leading to less sex in their marriage.
10. Cheating.  Though it often is not one of the main reasons behind a sexless marriage, it still needs to be placed on the list, because it is a possible reason behind what is causing you and your partner to have less alone time.

There are many more that one could state as a cause or reason behind lack of sex in a marriage.  And they will never be the same for everyone out there, so your reason may be on this list or not.  But one of the best ways to fight to keep your sex life active is to see a therapist and talk as a couple.  Make sure that you don't give up if you love the person you are with, but work through the causes and find what is really happening in your marriage.

Many couples will find the underlying cause and be able to get back to a normal sex routine and a marriage that is very satisfying and leaves them quite happy.  So look at the reasons above, call that therapist and sit down and talk with your partner.  You can work it out if you really want too.