diff --git a/pgloader/db.py b/pgloader/db.py
index 7fb737e..f036d6a 100644
--- a/pgloader/db.py
+++ b/pgloader/db.py
@@ -51,16 +51,13 @@ elif PSYCOPG_VERSION == 2:
 class db:
     """ a db connexion and utility class """
     def __init__(self,
-                 host, port, base, user, passwd,
+                 dsn,
                  client_encoding = PG_CLIENT_ENCODING,
                  copy_every = 10000, commit_every = 1000, connect = True):
         """ Connects to the specified database """
         self.log     = log
         self.dbconn  = None
-        self.dsn     = "host=%s port=%d user=%s dbname=%s password=%s" \
-                       % (host, port, user, base, passwd)
-        self.connect = "-h %s -p %s -U %s" % (host, port, user)
-        self.base    = base
+        self.dsn     = dsn
 
         # those parameters can be overwritten after db init
         # here's their default values
diff --git a/pgloader/pgloader.py b/pgloader/pgloader.py
index 5b1becd..afbdfa2 100644
--- a/pgloader/pgloader.py
+++ b/pgloader/pgloader.py
@@ -157,12 +157,21 @@ class PGLoader(threading.Thread):
             return
 
         try:
-            self.db = db(config.get(section, 'host'),
-                         config.getint(section, 'port'),
-                         config.get(section, 'base'),
-                         config.get(section, 'user'),
-                         config.get(section, 'pass'),
-                         connect = False)
+            dsn = [];
+            if config.has_option(section, 'host'):
+                dsn.append ("host=%s" % config.get(section, 'host'))
+            if config.has_option(section, 'port'):
+                dsn.append ("port=%d" % config.getint(section, 'port'))
+            if config.has_option(section, 'base'):
+                dsn.append ("dbname=%s" % config.get(section, 'base'))
+            if config.has_option(section, 'user'):
+                dsn.append ("user=%s" % config.get(section, 'user'))
+            if config.has_option(section, 'pass'):
+                dsn.append ("password=%s" % config.get(section, 'pass'))
+            if config.has_option(section, 'sslmode'):
+                dsn.append ("sslmode=%s" % config.get(section, 'sslmode'))
+
+            self.db = db(" ".join (dsn), connect = False)
 
             for opt in ['client_encoding', 'datestyle', 'lc_messages']:
                 if config.has_option(section, opt):